The Conservative Party is dogmatically opposed to proportional representation, claiming that PR, because it will almost always favour coalitions, creates the circumstances for weak and divisive leadership. This argument has real strength. For example, the Thatcher government never enjoyed an outright majority of the popular vote. Yet she could always rely on a parliamentary majority, and it was this majority that allowed her to use robust measures to tackle the over-mighty unions and economic collapse of the 1970s. If Britain had functioned under PR, it might never have been possible to tackle the unions.

There is also a more selfish argument, namely that the first-past-the-post system gets more Conservative MPs into Parliament than any other method known to man. This second argument is much less attractive than the first, but it is probably more powerful. This Electoral Reform Society report challenges the Conservative orthodoxy, making the extremely convincing case that present system is wiping out the Conservatives across northern England.

They make their argument through compelling use of statistics. They focus on the north of England, where the Conservatives find themselves in the position of the Lib Dems across most of Britain, or Labour in the South East. Thanks to FPTP the Conservatives find themselves effectively driven out of large parts of the North, unable to claim any more to be the national party.

The authors show that Tory support in the North is actually reasonably strong. Without PR it just doesn’t look or feel that way. For example in 2010 in Sheffield the Tories had no seats at all on the council. Under PR they would have had 12 out of 84. The Conservatives won 25 per cent of the vote in Tameside in 2012, yet held just five out of 57 seats. With PR they would have secured 14. And so on.

As the authors show, the effect is disastrous. Without local councillors the Tories lack troops on the ground and lose a strong local base. The authors point to the collapse of the Conservative vote in the Oldham East & Saddleworth by- election of 2011 as a manifestation of this syndrome.

As the Conservatives become less visible on the ground, rival parties become the main opposition. In some areas the Liberal Democrats, always opportunistic, have become the new party of working-class Toryism. Elsewhere Ukip are starting to do the same.

Many of the best Conservative minds are at present trying to work out how to regain the party’s former position in northern England. They are wise to do so. It would be terrible were the Conservatives to collapse into a political party which speaks only for southern England and parts of the Midlands. Reading this report has persuaded me that proportional representation in local elections may be part of the answer.